Frequencies for first 10,000 rows of totdiag variable in nhamcsopd1998 dataset :

    total # of diagnostic/screening |
                           services |      Freq.     Percent        Cum.
------------------------------------+-----------------------------------
                                  0 |      2,126       21.26       21.26
                                  1 |      3,267       32.67       53.93
                                  2 |      2,142       21.42       75.35
                                  3 |      1,142       11.42       86.77
                                  4 |        607        6.07       92.84
                                  5 |        289        2.89       95.73
                                  6 |        173        1.73       97.46
                                  7 |        101        1.01       98.47
                                  8 |         47        0.47       98.94
                                  9 |         41        0.41       99.35
                                 10 |         23        0.23       99.58
                                 11 |         11        0.11       99.69
                                 12 |         12        0.12       99.81
                                 13 |          6        0.06       99.87
                                 15 |          2        0.02       99.89
All boxes blank, including None box |         11        0.11      100.00
------------------------------------+-----------------------------------
                              Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016